2021年4月23日 星期五
落羽杉属种类及其杂交子代‘中山杉’系列品种的SSR指纹图谱构建及遗传关系分析
Construction of SSR fingerprint and analysis on genetic relationship of Taxodium species and their hybrid progenies T. ‘Zhongshanshan’ series cultivars
2020年 第29卷 第4期 页码[11-18]
摘要

运用荧光标记毛细管电泳技术,对池杉〔Taxodium distichum var. imbricatum (Nuttall) Croom〕、墨西哥落羽杉(T. mucronatum Tenore)和落羽杉〔T. distichum (Linn.) Rich.〕的单株以及‘中山杉’(T. ‘Zhongshanshan’)系列品种共96个样本进行SSR分子标记检测,分析供试样本的遗传多样性并分别构建指纹图谱;在此基础上,依据供试样本的Nei’s遗传距离进行聚类分析。结果显示:6对SSR引物共扩增条带91条,其中多态性条带68条;每对引物扩增条带9~31条,其中多态性条带6~27条,多态性条带百分率平均值为70.9%;各引物的多态性信息含量指数为0.476~0.793,平均值为0.658;供试样本的Nei’s基因多样性指数、Shannon’s多态性信息指数、观测杂合度和期望杂合度的平均值分别为0.755、1.599、0.381和0.245。用4对SSR引物的多态性条带可构建40个‘中山杉’系列品种的指纹图谱,指纹编码数量为33,鉴别率达85.0%;用6对SSR引物的多态性条带可构建15个池杉、23个墨西哥落羽杉和18个落羽杉共56个单株的指纹图谱,指纹编码数量为49,鉴别率达91.1%,表明采用荧光标记毛细管电泳技术并运用SSR分子标记构建的指纹图谱可明显提高鉴别率。聚类分析结果显示:池杉与墨西哥落羽杉和落羽杉的Nei’s遗传距离分别为0.420和0.169,‘中山杉’系列品种与池杉、墨西哥落羽杉和落羽杉的Nei’s遗传距离分别为0.358、0.114和0.137。在Nei’s遗传距离0.405处,12个池杉单株聚为Ⅰ大类,其余84个样本聚为Ⅱ大类;Ⅱ大类可进一步分为5组,其中,‘中山杉1302’(‘Zhongshanshan 1302’)、落羽杉单株L15和‘中山杉1305’(‘Zhongshanshan 1305’)分别单独成组,‘中山杉1304’(‘Zhongshanshan 1304’)、‘中山杉112’(‘Zhongshanshan 112’)、‘中山杉149’(‘Zhongshanshan 149’)、9个落羽杉单株和1个池杉单株聚为Ⅱ4组,供试的所有墨西哥落羽杉单株与其余样本聚为Ⅱ5组。综合分析结果表明:供试的‘中山杉’系列品种与池杉的遗传关系较远,与墨西哥落羽杉的遗传关系较近;而池杉与落羽杉的遗传关系较近,与墨西哥落羽杉的遗传关系较远。

Abstract

 SSR molecular marker detection was conducted for 96 samples including individuals of Taxodium distichum var. imbricatum (Nuttall) Croom, T. mucronatum Tenore and T. distichum (Linn.) Rich., and T. ‘Zhongshanshan’ series cultivars by using fluorescence labeled capillary electrophoresis, and their genetic diversity was analyzed and fingerprints were separately constructed; on the basis, cluster analysis was performed based on Nei’s genetic distance of test samples. The results show that 91 bands are amplified with 6 pairs of primers, in which, 68 bands are polymorphic bands; 9-31 bands are amplified with each pair of primer, in which, 6-27 bands are polymorphic bands, and the average percentage of polymorphic bands is 70.9%; polymorphic information content index of each primer is 0.476-0.793, with the average of 0.658; the averages of Nei’s gene diversity index, Shannon’s polymorphic information index, observed heterozygosity and expected heterozygosity of test samples are 0.755, 1.599, 0.381 and 0.245, respectively. Fingerprints of 40 T. ‘Zhongshanshan’ series cultivars can be constructed with polymorphic bands amplified by using 4 pairs of SSR primers, and the number of fingerprint code is 33, with the identification rate of 85.0%; fingerprints of 56 individuals including 15 T. distichum var. imbricatum, 23 T. mucronatum and 18 T. distichum can be constructed with polymorphic bands amplified by using 6 pairs of SSR primers, and the number of fingerprint code is 49, with the identification rate of 91.1%, indicating that fingerprints constructed with SSR molecular marker via fluorescence labeled capillary electrophoresis can evidently increase identification rate. The cluster analysis result shows that Neis genetic distances of T. distichum var. imbricatum with T. mucronatum and T. distichum are 0.420 and 0.169, respectively, and those of T. ‘Zhongshanshan’ series cultivars with T. distichum var. imbricatum, T. mucronatum and T. distichum are 0.358, 0.114 and 0.137, respectively. At Nei’s genetic distance of 0.405, 12 individuals of T. distichum var. imbricatum cluster into class Ⅰ, other 84 samples cluster into class Ⅱ; class Ⅱ can be further divided into 5 groups, in which, ‘Zhongshanshan 1302’, individual L15 of T. distichum and ‘Zhongshanshan 1305’ cluster into separate group, ‘Zhongshanshan 1304’, ‘Zhongshanshan 112’, ‘Zhongshanshan 149’, 9 individuals of T. distichum and 1 individual of T. distichum var. imbricatum cluster into group Ⅱ4, and all test individuals of T. mucronatum and other samples cluster into group Ⅱ5. The comprehensive analysis result shows that the genetic relationship of test T. ‘Zhongshanshan’ series cultivars with T. distichum var. imbricatum is relatively distant, but that with T. mucronatum is relatively close; while the genetic relationship of T. distichum var. imbricatum with T. distichum is relatively close, but that with T. mucronatum is relatively distant.

关键词落羽杉属; ‘中山杉’系列品种; SSR分子标记; 指纹图谱; 遗传关系
Key wordsTaxodium Rich.; T. ‘Zhongshanshan’ series cultivars; SSR molecular marker; fingerprint; genetic relationship
作者段豪, 徐建华, 王紫阳, 郭金博, 於朝广, 杨颖
所在单位江苏省中国科学院植物研究所(南京中山植物园) 江苏省落羽杉属树木种质创新与繁育工程研究中心, 江苏 南京 210014
点击量420
基金项目江苏省现代农业重点研发计划(BE2018390); 中国科学院战略生物资源服务网络项目(kfj-brsn-2018-6-003); 江苏省植物资源研究与利用重点实验室项目(JSPKLB201842); 国家自然科学基金资助项目(31700588)